Friction device.



No. 788,135. PATENTBD APR. 25, 1905. G. L. HARVEY.

FRIGTION DEVICE.

APPLIOATION E ILBD JULY 5, 1904.

2 SHEETS-SHEET l.

No. 788,135. PATENTED APR. 25, 1905. G. L. HARVEY.

FRICTION DEVICE. APPLIOATION FILED JULY 5, 1904.

2 SHEETS-SHEET 2.

QAM/Mw @umgh UNiTe STATES Patented April 25, 1905.

GEORGE LYON HARVEY, OF CHICAGO, ILLINOIS.

FRICTION DEVICE.

SPECIFICATION forming part of Letters Patent No. 788,135, dated April25, 1905.

Application filed July 5,1904. Serial No. 215,213.

To /r/ ll'lm'm, it 'nt/ty 0071100771,.-

Beit known that l, G soiree LYoN HARVEY, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois,(having a post-ottico address at 175 Dearborn street, Chicago,aforesaid, have invented certain new and useful Improvements in FrictionDevices, of which the following is a full and true description,reference being had to the accompanying' drawings, showing embodimentsof my invention.

rIhe object of this invention is the production of an exceedinglyetiicient and economical form of friction device especially useful as acompression-spring for draw-gear for railway-cars; and the improvementsconsist in the novel features and combinations hereinafter pointed out.

The invention is especially useful with that form of friction devicecontaining an cndwisecompressible member having frictional surfaces anda second member with which the first-named member has frictionalengagement when the device is subjected to butling or pulling' strains.

In the accompanying drawings, Figure 1 is a view showing the members ofmy new friction device while being' wound together. Fig. 9. is a view ofa portion of one member, showing a modified form of the invention. Fig.3 is a sectional view on the line 3 3 of Fig. 2; and Fig. i is a planview, partly in section, showing my present improvements in use withdraft-rigging of a railway-car.

As shown in the drawings, my new friction device is provided with an endwise-compressible member A, consisting of a succession of coils orloops. In Figs. 1 and AI I have shown the said member as made up of aconnected succession of coils or loops of pentagonal bar metal, thewhole made by winding upon a mandrel or otherwise and having thesurfaces M substantially parallel with the axis of the member A and withupper and lower frictional surfaces G disposed at angles ofsubstantially Vforty-five degrees with respect to said axis.

A distinctive point of novelty of my present invention consists inprovidinga form of member A, which while very supple or adapted toreadily yield to radial strains or distortion yet presents a largefrictional area for frictional engagement with a cooperating member.

I have discovered that if the frictional surfaces G of the members A arenot as long as the coil or coils of which they form a part thefrictional surface of the said coil or coils will not be appreciablyreduced, while the entire member will more readily yield to radial ordistortional strains. lhe result spoken of may be attained by removing,by sawing or otherwise, portions of the bar itself, thus dividing theVfrictional surfaces into bodies of, say, one inch in length -andthinning the coil or coils, or the result may be attained by applying toa heavy metallic strip of substantially equal thickness from end to enda succession of blocks slightly separated from one another, as shown inFig. 2. lf de sired, the coil or coils may bc formed in any othersuitable manner to provide the thinner and thicker portions or toprovide the coil or coils with portions which are exceedingly flexiblewhile retaining the exceedingly large frictional surfaces.

As shown in Figs. 1 and fi, the bar may be provided with cuts ll atintervals of, say, one inch. Saids cuts, which may all be on the sameedge of the coil, will not extend entirely through the bar, but leave aconsiderable portion of the sectional area thereof intact. Instead ofbeing `formed from the metal of the coil or loop friction-blocks orVfriction-bodies may be iitted thereto. In Figs. 2 and 3 I have shown asuccession of slightly-curved triangular blocks A2 [itted to the strip Aconstituting the coil or loop by means of rivets A3 or otherwise.

rlhe friction device is provided with a second member B, against whichthe member A operates and with which it has frictional cngagement underbufiing or pulling` strains. The second member may be yielding orunyielding and may be either compressible or incompressible endwise. Themember A may be fitted to the second member in any suitable way, and Ihave shown it as surrounding the member B. The last-named memberpreferably consists, however, of a connected succession of coils orloops, which have frictional surfaces F substantially parallel with thefrictional surfaces Gr of the member A.

I/Vhen wound or fitted together, the adjacent coilsor loops of themembers A and B may beinitially engaged, as shown in Fig. 1, or may benormally separated, as shown in Fig. 4. In the latter construction therewill be no engagement of the members under initial compression of thefriction device. As the compression is continued, however, the adjacentfrictional surfaces F and Gr of the two members will come intofrictional engagement, with the result that the coils of the member A inaddition to the longitudinal compression are radially distorted orexpanded, whereby the yielding resistance to the load is increased.

When the member A has a succession of frictional bodies or blocks, asshown, it is obvious that the frictional area or area offrictionalcontact between the surfaces F and G will not be appreciably reduced,although the coil or coils of the member A will be quite flexible andwill more readily yield to radial strain than where the frictionalsurfaces are continuous from e-nd to end of the coil or coils.

Preferably the device is provided with means to prevent the buckling orbending of the springs under load and to limit the extent of compressionof the device. For this purpose I may provide adjacent coils or loops ofthe member B with fiattened contact-faces C C. Under compression of thefriction device said faces are brought solidly together, and there islittle or no tendency of the adjacent coils to slip or slide past oneanother.

In Fig. I I have shown my new friction device employed in connectionwith draft-rigging of a railway-car. T indicates the tail of the couplerdraw-bar. W indicates the yoke. X and Y indicate the forward and rearfollower-plates, and Z Z indicate the draft-plates, which may be fittedbetween the usual draftsills and provided with stops .e e for thefollower-plates.

While I have herein shown and described two embodiments of my presentimprovements, I do not desire to be understood as limiting my inventionthereto. Obviously other forms will readily suggest themselves topersons skilled in the art and still be within my claims.

What I claim isl. Ina friction device, a member provided with asuccession of frictional blocks or frictional bodies, in combinationwith a cooperating' coiled mem ber having frictional surfaces forengaging the blocks or bodies aforesaid, substantially as described.

2. In a friction device, a member comprising a loop or coil providedwith a succession of frictional blocks or frictional bodies, incombination with a cooperating coiled member having frictional surfacesfor engaging the blocks or bodies aforesaid, substantially as described.

3. In a friction device, a member provided with a succession offrictional blocks or frictional bodies integral with the member, incombination with a cooperating coiled member having frictional surfacesfor engaging the blocks or bodies aforesaid, substantially as described.

4. In a friction device, a member consisting of a loop or coil providedwith a succession of frictional blocks or frictional bodies integralwith the loop or coil, in combination with a cooperating member havingfrictional surfaces for engaging the blocks or bodies aforesaid,substantially as described.

5. In a friction device, a member comprising a continuous loop or coilcut at intervals to render the loop or coil more iiexible and providedwith a succession of frictional blocks or frictional bodies, incombination with a cooperating member having frictional surfaces forengaging the blocks or bodies aforesaid, substantially as described.

6. In a friction device, a member comprising a continuous loop or coilhaving frictional surfaces which are cut at intervals to render the coilor loop more ieXible, in combination with a cooperating member havingfrictional surfaces for engaging the frictional surfaces of thefirst-named member, substantially as described.

7. In a friction device, inner and outer coiled members havingcooperating frictional surfaces, the frictional surfaces of one memberconsisting of a succession of frictional blocks or bodies, substantiallyas described.

8. In a friction device, a member provided with a succession of attachedfrictional blocks, in combination with a cooperating coiled memberhaving frictional surfaces for engaging the frictional blocks aforesaid,substantially as described.

9. In a friction device, outer and inner coiled members, one of saidcoils being notched, the frictional surfaces of both coils being incontact during the entire operation of the spring, substantially asdescribed.

lO. In a friction device, outer and inner coiled members having theirfrictional surfaces in contact during the entire operation of thedevice, one of said coiled members having an alternating large and smallcross-section, substantially as described.

1l. In a friction device, a spring with fric- IOO IIO

tional surfaces, the body of the spring having l In Witness whereof Ihave hereunto signed alternating' large and small cross-Section, submyname this 28th day of' J une, 1904.

Stantially as described. t 7 Y Y 1 T 1Q. In a friction device, a coiledmember, (IEORLTL LX ON MARVEL 5 said member having a body ot'alternating In presence oflnrg'e and small cross-sectwn, substantiallyas MARIE KIRLIN HINCHER, described. HAROLD CLINTON Fiamme.

